Synthesis Of Organosoluble Metal Phosphonates Support Homogeneous Catalyst And Application In The Asymmetric Hydrogenation

Two types of metal（Zr,Ti） phosphonates were synthesised.The complexing group of-PPh₂ was ultilized to immobolize the homogeneous chiral catalyst[Rh（COD）（BINAP）]⁺BF₄^-and Pd （BINAP） Cl₂ into inorganic backbone cavieties.The metal（Zr,Ti） phosphonate-supported catalysts were soluble in some organic solvents such as CH₂Cl₂ and methanol.Due to the different organosolubility in various solvents,the homogeneous catalysis of transitional matal supported on the inorganic backbone was carried out easily and the catalyst can be recycled by solid/liquid seperation.FT-IR,TGA,elemental analysis,x-PRD,N₂ sorption-desorption isotherm,SEM,and TEM were used to characterize surface morphorlogy,composition and structure of metal（Zr,Ti） phosphonates,and the the amount of[Rh（COD）（BINAP）]⁺BF₄^-and Pd（BINAP）Cl₂ immobolized on the pores was also determined.It was shown from the experimental results that organic-inorganic hybrid metal phosphonate possessed the amorphous structure of short-distance order and long-distance disorder from the disorderly accumulative formation of the regularly layered and self-assembled small crystal.Based on the data of N₂ adsorption-desorption isotherm and x-PRD, metal（Zr,Ti） phosphonates were the material with the low surface area（0.12-12.6 m²/g）,mesopore （5-80 nm） and layered（18.2-24.9（?）） structure in solid state.From the SEM images the metal（Zr,Ti） phosphonates in nanometer-sized particle with the regular mesopores were observed after dispersed in organic solvent.In the asymmitric hydrogenation of acetophenone and enamine catalyzed by metal（Zr,Ti） phosphonate-supported homogeneous catalyst,the preliminary results showed that there was no catalytic activity catalyzed by the supported[Rh（COD）（BINAP）]⁺BF₄^-,but the moderate activity were（60%） with 22-29.6%ee catalyzed by supported Pd（BINAP）Cl₂ was found.